Screencast:
Description: I'm getting an empty error message like this two or more times a day since the last week:
{ "errorMessage": ": ", "url": "https://pt.wikipedia.org/static/1.27.0-wmf.5/extensions/CentralNotice/resources/subscribing/ext.centralNotice.display.js", "lineNumber": 183, "columnNumber": 0, "errorObject": {} }
I got the info above when I accessed
https://pt.wikipedia.org/w/index.php?title=Pr%C3%A1tica&type=revision&diff=43866142&oldid=43262742
for the first time (the error didn't happen after a page reload), in debug mode.
By clicking on the console, I could see that the problematic line was this:
navigator.sendBeacon( url.toString() );
When in production mode, the error is similar, but the URL we get doesn't make it clear that the error comes from centralNotice. E.g.: this was the message I got at
https://pt.wikipedia.org/w/index.php?diff=next&oldid=43209909
{ "errorMessage": ": ", "url": "https://pt.wikipedia.org/w/load.php?debug=false&lang=pt&modules=ext.centralNotice.bannerChoiceData%2CbannerController%7Cext.centralNotice.bannerController.lib%7Cext.centralauth.centralautologin.clearcookie%7Cext.uls.init%2Cinterface%2Cpreferences%2Cwebfonts%7Cext.visualEditor.desktopArticleTarget.init%7Cext.visualEditor.track%2Cve%7Cjquery.byteLength%2Ccookie%2CtabIndex%2Cthrottle-debounce%2Ctipsy%7Cmediawiki.Title%2CUri%2Capi%2Ccldr%2Ccookie%2CjqueryMsg%2Clanguage%2Cuser%7Cmediawiki.language.data%2Cinit%7Cmediawiki.libs.pluralruleparser%7Cmediawiki.page.startup%7Cskins.vector.js%7Cuser.defaults&skin=vector&version=71829dff924d&*", "lineNumber": 6, "columnNumber": 0, "errorObject": {} }
Usually, the error didn't happen again after a page reload but in the most recent occurrences, it was happening consistently on every page load, both in production and in debug mode.
Browser information
navigator.userAgent > Mozilla/5.0 (X11; Linux x86_64; rv:42.0) Gecko/20100101 Firefox/42.0